Service connection apparatus and method in portable terminal

ABSTRACT

A call connection method and apparatus are disclosed. When a service is released in a portable terminal that supports different communication modes due to a network problem, the call connection method and apparatus reconnects the service to another network. The call connection method includes performing a first service through a first network, analyzing, when the connected first service is released, the cause of disconnection, acquiring, when the cause of disconnection is a problem in the first network, connection information, and attempting to connect a second service through a second network based on the connection information.

PRIORITY

This application claims the benefit under 35 U.S.C. §119(a) of a Koreanpatent application filed in the Korean Intellectual Property Office onDec. 24, 2007 and assigned Serial No. 10-2007-0136078, the entiredisclosure of which is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to call connection technology. Moreparticularly, the present invention relates to a method and apparatusfor attempting to reconnect a call when a call drop occurs in a portableterminal that can support different communication modes.

2. Description of the Related Art

As the popularity of portable terminals continues to increase,manufacturers are developing a variety of functions to satisfyadditional user demands. As an example, multi-mode portable terminalshave recently appeared on the market. A multi-mode portable terminal isa terminal that can use two or more wireless communication networks.

Conventional portable terminals that support one type of wirelesscommunication network can perform communication within only acorresponding wireless communication network service area. In contrast,the multi-mode portable terminals can perform communication within twoor more wireless communication network service areas. For example, dualmode portable terminals can support a Code Division Multiple Access(CDMA) network and a Global System for Mobile communication (GSM)network, so that they can perform communication within both CDMA and GSMnetwork service areas. Accordingly, the dual mode portable terminals canbe more widely used than the single mode portable terminals.

However, since the conventional multi-mode portable terminals switchbetween networks in such a way that they are booted, enter an idle mode,and then perform communication by operation of their menu, they arecomplicated to operate and require significant time to switch theirmodes. To resolve these problems, a multi-standby portable terminal hasbeen proposed. The multi-standby portable terminal, unlike themulti-mode portable terminals, can simultaneously support two networks,for example, a CDMA network and a GSM network.

Wireless communication systems, which employ the 2^(nd) generationcommunication mode, such as a GSM communication mode and a CDMAcommunication mode, have been used in a wide service area for severalyears. Accordingly, the basic facilities that support the 2^(nd)generation communication mode have been constructed and are wellestablished.

On the other hand, in order to provide services that a wirelesscommunication system of the 2^(nd) generation communication mode(hereinafter referred to as a ‘2^(nd) generation network’) cannotsupport, a wireless communication system adopting the 3^(rd) generationcommunication mode (hereinafter referred to as a ‘3^(rd) generationnetwork’), such as CDMA 2000 communication, Wideband Code DivisionMultiple Access (WCDMA) communication, etc., is being graduallyintroduced. In an area equipped with the 3^(rd) generation network, thewireless systems can use the basic facilities for the 2^(nd) generationnetwork and support specialized communication of the 3^(rd) generationnetwork.

However, the 3^(rd) generation network is less widely constructed thanthe 2^(nd) generation network. In particular, there are still many weakelectric field areas and no service areas, with respect to the 3^(rd)generation network. Therefore, when users use a specialized service ofthe 3^(rd) generation network, for example, a Video Telephony (VT) callservice, they frequently experience a call drop when traveling to a weakelectric field area or to an area with no service.

That is, while a service, such as a VT call service, is performedthrough the 3^(rd) generation network, a call drop frequently occurs dueto gap areas. In addition, when a portable terminal using a VT callservice is moved from the coverage of the 3^(rd) generation network to aservice area where only the 2^(nd) generation network is available, itsVT call is disconnected.

When call connection is dropped and therefore terminated during the VTcall service, a user attempts to manually reconnect the call. That is,when connection of the VT call is enforcedly terminated, the userattempts to connect the disconnected VT call again, without knowing thecause of disconnection. However, when the user moves out of the 3^(rd)generation network service area, the call connection fails and thus theuser must attempt to reconnect a voice call using the 2^(nd) generationnetwork.

SUMMARY OF THE INVENTION

An aspect of the present invention is to address at least theabove-mentioned problems and/or disadvantages and to provide at leastthe advantages described below. Accordingly, an aspect of the presentinvention is to provide a method and apparatus for reconnecting a callwhen a connected call is released in portable terminals providingdifferent communication services.

Another aspect of the present invention is to provide a method andapparatus for reconnecting a call when a call drop occurs in portableterminals providing different communication modes.

Yet another aspect of the present invention is to provide a method andapparatus that can automatically connect a Video Telephony (VT) call ofthe 3^(rd) generation network to a voice call of the 2^(nd) generationnetwork when a call drop of the VT call occurs, thereby providing theuser with convenient use and continuous services.

In accordance with an exemplary embodiment of the present invention, acall connection method in a portable terminal that supportscommunication modes of different networks is provided. The methodincludes performing a first service through a first network, analyzing,when the connected first service is released, the cause ofdisconnection, acquiring, when the disconnection cause is a problem inthe first network, connection information and attempting to connect asecond service through a second network based on the connectioninformation.

In accordance with another exemplary embodiment of the presentinvention, a call connection method in a portable terminal that supportsa communication mode of different networks is provided. The methodincludes performing a video telephony call with a target portableterminal through a 3^(rd) generation network, analyzing, when theconnected video telephony call is disconnected, a disconnection cause,acquiring, when the disconnection cause is a problem in the 3^(rd)generation network, connection information about the target portableterminal, and attempting to connect a voice call through a 2^(nd)generation network based on the connection information.

In accordance with yet another exemplary embodiment of the presentinvention, a portable terminal that supports a communication mode ofdifferent networks is provided. The terminal includes a firstcommunication module for establishing a communication channel with a2^(nd) generation network and for providing a voice call service, asecond communication module for establishing a communication channelwith a 3^(rd) generation network and for providing a video telephonyservice, a memory for storing information about a service disconnectioncause, guide information according to a new service connection attemptthat is performed as the connected service is released, and connectioninformation of a target portable terminal that is connected to theservice; and a controller for processing a voice call service of the2^(nd) generation network through the first communication module and avideo telephony service of the 3^(rd) generation network through thesecond communication module and for connecting, when a service isconnected to a target portable terminal through one of the 2^(nd) and3^(rd) generation networks, the released service to another network thatis different from the network before the service is released.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features and advantages of certainexemplary embodiments of the present invention will be more apparentfrom the following description taken in conjunction with theaccompanying drawings, in which:

FIG. 1 is a schematic block diagram illustrating a portable terminalaccording to an exemplary embodiment of the present invention; and

FIG. 2 is a flowchart describing a method for connecting a new call whena connected call is released in a portable terminal, according to anexemplary embodiment of the present invention.

Throughout the drawings, it should be noted that like reference numbersare used to depict the same or similar elements, features andstructures.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The following description with reference to the accompanying drawings isprovided to assist in a comprehensive understanding of exemplaryembodiments of the invention as defined by the claims and theirequivalents. It includes various specific details to assist in thatunderstanding but these are to be regarded as merely exemplary.Accordingly, those of ordinary skill in the art will recognize thatvarious changes and modifications of the embodiments described hereincan be made without departing from the scope and spirit of theinvention. Also, descriptions of well-known functions and constructionsare omitted for clarity and conciseness.

The terms and words used in the following description and claims are notlimited to the bibliographical meanings, but, are merely used by theinventor to enable a clear and consistent understanding of theinvention. Accordingly, it should be apparent to those skilled in theart that the following description of exemplary embodiments of thepresent invention are provided for illustration purpose only and not forthe purpose of limiting the invention as defined by the appended claimsand their equivalents.

It is to be understood that the singular forms “a,” “an,” and “the”include plural referents unless the context clearly dictates otherwise.Thus, for example, reference to “a component surface” includes referenceto one or more of such surfaces.

Exemplary embodiments of the present invention are related to a methodand apparatus that can automatically reconnect a call when a call dropof the connected call occurs in a portable terminal providing differentcommunication modes. In particular, when a call drop of a VideoTelephony (VT) call occurs unexpectedly, for example due todeterioration of an electric field in a wireless service area, anexemplary method and apparatus of the present invention canautomatically perform call connection of a voice call. That is, when aconnected call of a VT call is disconnected due to various causes, forexample, the deterioration of the electric field of a 3^(rd) generationnetwork, an exemplary method and apparatus of the present invention canautomatically connect a voice call to a target portable terminal througha 2^(nd) generation network.

In the following description, exemplary embodiments of the presentinvention are described based on portable terminals that supportwireless communication systems of the 2^(nd) generation communicationmode (hereinafter referred to as a ‘2^(nd) generation network’), such asGlobal System for Mobile communication (GSM) and Code Division MultipleAccess (CDMA), and wireless communication systems of the 3^(rd)generation communication mode (hereinafter referred to as a ‘3^(rd)generation network’), such as, Code Division Multiple Access 2000 (CDMA2000) communication mode, and Wideband Code Division Multiple Access(WCDMA) communication mode. However, it should be understood that thepresent invention is not limited to the networks described above. Thatis, the present invention can be applied to portable terminals thatsupport other types of communication modes.

FIG. 1 is a schematic block diagram illustrating a portable terminalaccording to an exemplary embodiment of the present invention

The portable terminal includes two slots that support the 2^(nd) and3^(rd) generation networks and communications therewith, respectively,when the 2^(nd) and 3^(rd) generation network cards are installed intothe slots. Of course, it is understood that the present invention is notlimited to the present exemplary embodiment. For example, the portableterminal may be implemented in such a way that a dual card supportingthe 2^(nd) and 3^(rd) generation networks may be installed in a singleslot or that more than two slots may be provided for various networks.That is, the present invention is not limited in its application to the2^(nd) and 3^(rd) generation networks.

As illustrated in FIG. 1, the portable terminal adapted to the functionsof the present invention includes a first antenna 105, a firstcommunication module 110 for providing the 2^(nd) generationcommunication service, a second antenna 115, a second communicationmodule 120 for providing the 3^(rd) communication service, an audioprocessing unit 130, an input unit 140, a display unit 150, a memory 160and a controller 170.

Referring to FIG. 1, the first antenna 105 establishes a communicationchannel with the 2^(nd) generation network and processestransmitted/received signals of a frequency band for the 2^(nd)generation communication service. The second antenna 115 establishes acommunication channel with the 3^(rd) generation network and processestransmitted/received signals of a frequency band for the 3^(rd)generation communication service.

The first communication module 110 performs wireless communicationthrough the first antenna 105. It establishes a communication channelwith the 2^(nd) generation network through the first antenna 105 andtransmits/receives Radio Frequency (RF) signals of a frequency bandsupported by the 2^(nd) generation network. The first communicationmodule 110 includes an RF transmitter for up-converting the frequency oftransmitted signals and amplifying the transmitted signals. The firstcommunication module 110 also includes an RF receiver for low-noiseamplifying received RF signals and down-converting the received RFsignals.

The second communication module 120 performs wireless communicationthrough the second antenna 115. It establishes a communication channelwith the 3^(rd) generation network through the second antenna 115 andtransmits/receives RF signals of a frequency band supported by the3^(rd) generation network. The second communication module 120 includesan RF transmitter for up-converting the frequency of transmitted signalsand amplifying the transmitted signals. The second communication module120 also includes an RF receiver for low-noise amplifying received RFsignals and down-converting the received RF signals.

The audio processing unit 130 is provided to play back audio signalsreceived from the controller 170 and to provide externally receivedaudio signals as input to the controller 170. That is, the audioprocessing unit 130 converts audio signals received from the controller170 into audible sound and outputs them through a speaker SPK. Inaddition, the audio processing unit 130 converts audio signals receivedby a microphone MIC, such as voice signals, into data and outputs themto the controller 170.

The input unit 140 serves to receive information input by a user andoutput the information to the controller 170. The input unit 140 mayinclude a plurality of function, number and other keys and receive inputabout a variety of characters and other functions through the keysignals, related to function settings and function control of theportable terminal. In an exemplary implementation, the input unit 140 isformed having a touch pad, a general key arrayed pad, a QWERTY key arraypad, or a combination thereof.

The memory 160 stores at least one application program necessary for thefunctions according to exemplary embodiments of the present invention.The memory 160 also stores user data generated by a user, data receivedfrom one of the networks, information generated as the application isexecuted and the like. It may also include one or more buffers thatstore data generated as an application is executed.

In an exemplary implementation, the memory 160 may include a displayinformation storage area 161 and a connection information storage area163. In an exemplary implementation, the display information storagearea 161 stores pop-up messages, for example, guide information showingthat a connected call is released due to deterioration of the electricfield (i.e. poor signal strength) of a network. The connectioninformation storage area 163 buffers call connection information of atarget portable terminal when a call connected to the target terminal isdisconnected. In an exemplary implementation, the connection informationstorage area 163 buffers the phone number of the target portableterminal, information about the network to which the target portableterminal is connected, and the like. The connection information storagearea 163 supplies the call connection information to the controller 170,for example at the request of the controller 170, when a call connectionis attempted again.

In an exemplary implementation, the guide information may be a pop-upmessage showing a standby request that is caused as a connected call isdisconnected due to a deterioration of the electric field of the 3^(rd)generation network (e.g. a deterioration caused by entering a gap area,leaving the coverage area of the 3^(rd) generation network, and so on),and thus a new call is attempted through the 2^(nd) generation network.

The display unit 150 displays screen data generated when the applicationis executed, data generated by the user's key operation states, by thefunction setting information, etc. The display unit 150 may beimplemented with an LCD and the LCD may include a touch screen. In thatcase, the input unit 150 may provide some or all of the functions of theinput unit 140. Furthermore, the display unit 150 may display guideinformation from the display information storage area 163, through apop-up method, according to the control of the controller 170.

The controller 170 controls the operation of the portable terminal. Italso controls signal flows between the elements in the portableterminal, such as the first and second communication modules 110 and120, the audio processing unit 130, the input unit 140, the memory 160,and the display unit 150. It also includes a data processor thatincludes a codec and a modem.

In particular, the controller 170, according to exemplary embodiments ofthe present invention, controls the connection of a voice call throughthe 2^(nd) generation network and the connection of a video telephonycall through the 3^(rd) generation network. When a call connected to aparticular target portable terminal is disconnected, the controller 170analyzes the call disconnection cause. If the controller 170 ascertainsthat the call disconnection is caused by the network, it attempts toconnect a new call to the particular target portable terminal usinganother network as opposed to the currently disconnected network. Whilenew call connection is attempted, the controller 170 may display apop-up message showing the determined call disconnection cause andshowing that a new call connection is attempted.

For example, if a VT call service, provided to a particular portableterminal through the 3^(rd) generation network, is released, thecontroller 170 controls to be connected to a voice call service, basedon the connection information of the particular portable terminalthrough the 2^(nd) generation network. It should be understood that thecontrol algorithm of the controller 170 can be activated or inactivatedaccording to a user's function settings.

In order to efficiently perform the function described above, thecontroller 170 may include a call connection unit 171 and a callmanagement unit 173.

The call connection unit 171 processes the connection of a voice callservice through the 2^(nd) generation network and the connection of a VTcall service through the 3^(rd) generation network. In particular, whenthe connected service is released, the call connection unit 171processes a new connection service, according to the disconnectioncauses, so that the connection can be connected not to the currentlydisconnected network but to another network. The call connection unit171 can process the new service connection, referring to connectioninformation in the connection information storage area 165.

When the connected service is released, the call management unit 173analyzes the disconnection cause. If the call management unit 173ascertains that the disconnection is caused by the network, it providesthe information to the call connection unit 171.

Although a portable terminal according to an exemplary embodiment of thepresent invention is schematically shown in FIG. 1 for convenience, itshould be understood that the present invention is not limited to thepresent embodiment. For example, the portable terminal may furtherinclude a camera module, an electronic payment module, a digitalbroadcasting module, a short-range communication module, a batterymodule, etc. It will also be easily appreciated to those skilled in theart that a portable terminal according to the present invention can beconfigured to remove one or more elements from the configurationdescribed above or to replace them with other elements.

In the following description, a call connection method according to anexemplary embodiment of the present invention is explained. It should beunderstood that the present invention is not limited to the illustratedembodiment and that there are many modifications from the presentexample.

FIG. 2 is a flowchart describing a method for connecting a new call whena connected call is released in a portable terminal according to anexemplary embodiment of the present invention. In the followingdescription, it is assumed that a function according to the presentinvention is previously activated by a user. That is, the function ofthe present invention may be activated/inactivated by a user. Therefore,the procedure of FIG. 2 may further include a step of determiningwhether a function is activated.

Referring to FIG. 2, the controller of a portable terminal performs a VTcall with a target portable terminal in step S201. The controllerdetermines whether a VT call is disconnected during the process of theVT call in step S203.

If it is determined that the VT call is disconnected in step S203, thecontroller analyzes the cause of disconnection of the VT call in stepS205 and then determines whether the disconnection is caused by thenetwork in step S207. More specifically, the cause of disconnection isanalyzed to determine whether the disconnection was performed at theuser's request or the request of the target portable terminal or whetherthe disconnection was caused by the network of the VT call (i.e. the3^(rd) generation network).

The call disconnection by the network may occur when an electric fieldstrength deteriorates as a portable terminal, in a call connection witha target portable terminal, enters a gap area, and thus a call dropoccurs by radio link failure. A call drop may also occur due to varioustypes of handover failures, such as a network malfunction regardingsynchronization. These network problems can be ascertained by evaluatingthe strength of a signal received from a base station.

When the controller ascertains what the call disconnection is performedunder the direction of the user, that is, under normal circumstances, atstep S207, it normally terminates the call in step S209. On thecontrary, when the controller ascertains that the call disconnection iscaused by a network problem, it acquires connection information aboutthe target portable terminal in step S211.

In step S213, the controller establishes a communication channel withanother network (e.g. the 2^(nd) generation network) and attempts toconnect a voice call, based on the acquired connection information.While the controller is being connected to a voice call, it can displaya previously set pop-up message on the display unit in step S215.

When the voice call is connected to the target portable terminal in stepS217, the controller processes operations related to the voice call withthe target portable terminal in step S219.

Although not illustrated in FIG. 2, when the portable terminal isconnected to a target portable terminal to perform service connection, amethod according to an exemplary implementation may further include theprocesses of acquiring and storing information about the target portableterminal and information about a corresponding network through which theservice connection trial is performed. It will also be appreciated thatafter attempting to connect a voice call at step S213, the process ofoutputting a pop-up message may be omitted according to a user's settingor the initial setting of the portable terminal.

As described above, according to an exemplary embodiment of the presentinvention, when a connected VT call is disconnected, the disconnectedcall is automatically connected to a voice call. However, the exemplaryembodiment shown in FIG. 2 may be variously modified in such a way that,when a connected voice call is disconnected, a new voice call isautomatically connected or a new VT call is automatically connected. Itmay also be modified in such a way that, when a connected VT call isdisconnected, a new VT call is automatically connected.

In an exemplary embodiment of the present invention, a new call isconnected through another network that is not the previously connectednetwork. However, it will be appreciated that a new call can also beconnected through the same network.

As described above, in a method and apparatus for connecting a call in aportable terminal according to exemplary embodiments of the presentinvention, when a portable terminal supporting different communicationmodes fails call connection in one of the communication modes, itswitches the current communication mode to another communication modeand attempts to connect a call again, thereby enhancing the success rateof call connection. In particular, when a call drop occurs in a portableterminal supporting different communication modes, call connection canbe easily attempted again. When a call drop of a connected VT call usingthe 3^(rd) generation network occurs, it is automatically connected to avoice call using the 2^(nd) generation network, thereby providing a userwith greater convenience and continuous service.

While the invention has been shown and described with reference toexemplary embodiments thereof, it will be understood by those skilled inthe art, that various changes in form and details may be made thereinwithout departing from the spirit and scope of the invention as definedin the appended claims and their equivalents.

1. A call connection method in a portable terminal that supportsmultiple communication modes, the method comprising: performing a firstservice through a first network; analyzing, when the connected firstservice is released, the cause of disconnection; acquiring, when thedisconnection cause is a problem in the first network, connectioninformation; and attempting to connect a second service through a secondnetwork based on the connection information.
 2. The method of claim 1,wherein the first service comprises a Video Telephony (VT) call serviceand the first network comprises a 3^(rd) generation network.
 3. Themethod of claim 2, wherein the second service comprises a voice callservice and the second network comprises a 2^(nd) generation network. 4.The method of claim 2, wherein the connection information comprises:information about the first network; and information about a targetportable terminal.
 5. The method of claim 2, wherein the acquiring ofthe connection information comprises a first step of acquiring theconnection information from a target portable terminal upon theperforming of the first service, storing the connection information, anda second step of acquiring the stored connection information.
 6. Themethod of claim 2, further comprising: outputting information about thedisconnection from the first service; and outputting information aboutthe connection to the second service after the attempting to connect thesecond service through the second network.
 7. A call connection methodin a portable terminal that supports multiple communication modes, themethod comprising: performing a video telephony (VT) call with a targetportable terminal through a 3^(rd) generation network; analyzing, whenthe connected VT call is disconnected, a disconnection cause; acquiring,when the disconnection cause is a problem in the 3^(rd) generationnetwork, connection information about the target portable terminal; andattempting to connect a voice call through a 2^(nd) generation networkbased on the connection information.
 8. The method of claim 7, furthercomprising: storing the connection information about the target portableterminal when the VT call is performed with the target portableterminal.
 9. The method of claim 8, wherein the connection informationcomprises: information about the 3^(rd) generation network connectingthe VT call; and information about the target portable terminal.
 10. Themethod of claim 8, further comprising: outputting disconnectioninformation about the VT call; and outputting connection informationabout the voice call when attempting to connect the voice call throughthe 2^(nd) generation network.
 11. The method of claim 7, wherein theattempting to connect the voice call occurs as an automatic functionwhen the disconnection cause is a problem in the 3^(rd) generationnetwork.
 12. The method of claim 11, further comprising determiningwhether the automatic connection function is activated.
 13. A portableterminal that supports multiple communication modes, the terminalcomprising: a first communication module for establishing acommunication channel with a 2^(nd) generation network and for providinga voice call service; a second communication module for establishing acommunication channel with a 3^(rd) generation network and for providinga video telephony service; a memory for storing information about aservice disconnection cause, guide information according to a newservice connection attempt that is performed as the connected service isreleased, and connection information of a target portable terminal thatis connected to the service; and a controller for processing a voicecall service of the 2^(nd) generation network through the firstcommunication module and a video telephony service of the 3^(rd)generation network through the second communication module and forconnecting, when a service is connected to a target portable terminalthrough one of the 2^(nd) and 3^(rd) generation networks, the releasedservice to another network that is different from the network connectedbefore the service is released.
 14. The portable terminal of claim 13,wherein the controller analyzes the cause of disconnection when theservice connected to the target portable terminal is released andconnects the released service to another network service when thedisconnection is caused by the network problem.
 15. The portableterminal of claim 14, wherein the controller displays the cause ofdisconnection and the attempt of service connection via another network,when the service is connected to another network.
 16. The portableterminal of claim 14, wherein the controller comprises: a callconnection unit for processing connection of the voice call servicethrough the 2^(nd) generation network, connection of the video telephonyservice through the 3^(rd) generation network, and connection withanother network that is different from a previous network according tothe cause of disconnection, when the connected service is released; anda call management unit for analyzing the cause of disconnection when theconnected service is released and for providing the analyzed result tothe call connection unit.
 17. The portable terminal of claim 16, whereinthe call connection unit processes the connection with another networkbased on connection information that is previously stored in the memory.18. The portable terminal of claim 13, wherein the memory comprises: adisplay information storage area for storing guide information aboutdisconnection of a service with the portable terminal; and a connectioninformation storage area for buffering connection information about thetarget portable terminal when the service connected with the targetportable terminal is released.
 19. The portable terminal of claim 18,wherein the connection information comprises: a phone number of thetarget portable terminal; and connected network information about thetarget portable terminal.